Spencer S. Koyle, 33, of Holden, died on the Devils Den wildfire, about 3 miles east of the town of Oak City, about 100 miles southwest of Salt Lake City.

"He just got trapped in it, basically," Koyle's sister-in-law, Shelly Buttars, told The Tribune Friday morning.

Buttars said the family does not yet know the precise cause of death.

The sheriff's office said Friday that Koyle was among 30 firefighters attempting to keep the blaze from coming into town. About 2:25 p.m., the wind shifted, changing the direction and intensity of the fire, which had burned about 250 acres.

Fire lookouts ordered the firefighters out. Koyle attempted to evacuate but was overtaken by the blaze, the sheriff's office stated in a news release.

U.S. Forest Service spokeswoman Andi Falsetto would not confirm the details of Koyle's death and said federal investigators were arriving in Millard County on Friday to assist the sheriff's office.

The Devils Den fire was started by lightning just before midnight Tuesday in the Canyon Mountains and had burned about 250 acres of pinyon, juniper and brush.

The firefighters working there Thursday were replaced Friday by a larger team, Falsetto said.

Buttars said Koyle was employed full-time by the U.S. Bureau of Land Management. He is survived by his wife, Nichole Koyle, and three children, ages 7, 4 and 18 months.